Express the following numbers in standard form.
`31860000000`

Answer

To express the number `31860000000` in standard form, we follow these steps:

### Step 1: Identify the first non-zero digit
The first non-zero digit in the number `31860000000` is `3`.

### Step 2: Place the decimal point
We place the decimal point after the first non-zero digit. This gives us `3.186`.

### Step 3: Count the number of places the decimal point has moved
Next, we need to determine how many places we moved the decimal point from its original position (which is at the end of the number) to its new position (after the `3`).

In `31860000000`, the decimal point is initially at the end of the number. When we move it to after the `3`, we count the number of digits we have moved:
- From the end of the number to after the `3`, we have moved it 10 places to the left.

### Step 4: Write the number in standard form
Now, we can express the number in standard form. The standard form is given by the number we obtained (with the decimal point) multiplied by 10 raised to the power of the number of places we moved the decimal point.

Thus, we write:
\[ 3.186 \times 10^{10} \]

### Final Answer
The number `31860000000` in standard form is:
\[ 3.186 \times 10^{10} \]

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